treatment of bifurcated coronary lesions with cypher™-stent

Conditions: Coronary Artery Disease

Summary: this study is a prospective, randomized, single-center evaluation of the cypher™ sirolimus eluting coronary stent system in the treatment of de novo bifurcated coronary lesions comparing provisional modified t stenting with systematic modified t-stenting.

bifurcations involving a significant side branch (sb diameter ≥ 2.25 mm) occur in approximately 15-20% of all coronary lesions considered for percutaneous intervention. if a side branch (sb) subtends significant myocardium, failure to preserve sb vessel patency can lead to complications such as myocardial infarction or persistent chest pain despite full patency of the main branch. bifurcation lesions are inherently complex and interventional treatment remains a challenging problem for physicians. the optimal technique for stenting bifurcated lesions is still unknown. several dual vessel stenting techniques have been described in the literature, such as "t", "v", "y", "culotte" and "crush" procedures. however, most studies of bifurcation stenting have found that optimal long-term results are obtained by stenting the main vessel and then performing plain balloon angioplasty of the side branch ("kissing balloon"-technique). nevertheless, occlusion or reduced flow of the sb are frequent after stenting of the mb. therefore, the sb is stented in approximately 50% of procedures even if ptca alone was intended. hypothesis: compared with plain dilatation of side branch, the placement of cypher-stent in side branch using modified t-stenting technique will reduce "in-segment percent diameter stenosis" of the side branch at 9 months post procedure as measured by quantitative coronary angiography.

Eligibility criteria:
inclusion criteria: * 1. the target vessel must meet the following criteria: 1. bifurcated lesion type 1, 2, 3 or 4 of a native coronary artery with a reference vessel diameter of 2.5 mm to 4.0 mm in the main branch and of ≥ 2.25 mm in the side branch. 2. the target lesion (main branch and / or side branch) must be at least 50% diameter stenosis. 3. the target lesion has not been previously treated with any interventional procedure. 4. the target vessel (main branch and side branch) must be feasible for stent implantation (successful passage with the guide wire; successful predilatation with an appropriately sized balloon; no heavy calcification; no diffuse distal disease that might impede run off). 2. patient has stable or unstable angina pectoris (ccs classification i or greater) or a positive stress test for ischemia. 3. patient must be ≥ 18 years of age. 4. female subjects of childbearing potential must have a negative pregnancy test within 7 days before the procedure. 5. patient has no other treatment planned within 30 days of the procedure. 6. patient has been informed of the nature of the study and agrees to its provisions and has written informed consent as approved by the ethics committee. 7. patient willing to comply with required post-procedure follow-up. exclusion criteria: * 1. patient has had an acute myocardial infarction (\> 3x normal ck with presence of ckmb) within 72 hours preceding the index procedure and ck has not returned to normal limits at the time of the procedure. 2. patient will have a known hypersensitivity or contraindication to aspirin, heparin, clopidogrel, stainless steel, sirolimus, or contrast sensitivity that cannot be adequately pre-medicated. 3. patient has a platelet count of \ 700,000 cells/mm³, a wbc of \<3,000 cells/mm³, or documented or suspected liver disease. 4. patient has a history of bleeding diathesis or coagulopathy. 5. patient has suffered a cva or tia within the past six months. 6. active peptic ulcer or upper gi bleeding within the prior 6 months. 7. patient has a co-morbidity (i.e. cancer or congestive heart failure) that may cause the patient to be non-compliant with the protocol, or is associated with limited life- expectancy (less than 2 years). 8. patient must be excluded from the study if any of these angiographic criteria are met: 1. the target vessel contains intraluminal thrombus. 2. the target lesion is located in the left main coronary artery. 3. the target lesion or vessel shows angiographic evidence of severe calcification. 4. the patient has undergone previous pci to the target vessel within 6 months. 5. pre treatment of the lesion is done with a technique other than balloon angioplasty (e.g. rotablation).

Keywords: coronary bifurcation ; pci; modified t-stenting; sirolimus stent